Replacement for TIP120 Transistor

[Isaac P]

Hello,

I am currently using a simple Arduino circuit with a series of TIP120 transistors for a series of valves. We are trying to cut down the size of the circuit, but are currently limited by the relatively large TIP120s, of which we have about 16 in use. Can anyone recommend a smaller/micro version (same specs) transistor which we can use to replace the TIP120s? Our final goal is to attach to a printed board, so as small as possible is preferred.

Thanks

 

[mofy]

You need to specify voltage and current ratings for the valves. Off the cuff though I would probably look at surface mount power MOSFETs. They do need overvoltage protection though.

 

[BGB]

You need to specify voltage and current ratings for the valves. Off the cuff though I would probably look at surface mount power MOSFETs. They do need overvoltage protection though.

if current requirements are low enough (below 25 volt and 1.2 amps), maybe something like a 2N3506 (TO-92 NPN Darlington) could also work?... maybe also the 2N6426 which is 40 volt 1.2 amp.

these could be closer to a drop-in replacement, and use smaller (TO-92) packaging.


MOSFETs may or may not be a good replacement for Darlington transistors depending on how they are being used. with MOSFETs it may be necessary to add pull-down resistors to make sure they turn off, and they may behave very differently when it comes to analog circuits (potentially requiring other changes to the circuit to compensate).

but, here a lot depends on what the circuit is doing and how it is wired up.